The present invention relates to a work conveyance method for conveying a work constructed in a subline to an assembly zone for making a vehicle body in an assembly line thereof, and a work conveyance mechanism for the same.
As for the vehicle assembly line to assemble an automobile, it is constituted with a mainline, wherein various parts are assembled into the body of the automobile that is moved along a conveyance line with being hung from a hanger or being set on a pallet, a subline, wherein the work that contains a plurality of parts is constructed with, and the work conveyance mechanism, in which the work that is constructed in the subline is conveyed to the assembly zone for the automobile. Further, as the part that is assembled on the body, it is mentioned that a communication line such as a wiring for electric system or the like, interior parts such as installment panel or a seat, suspension system parts such as an engine or suspension and exterior parts such as a rear-vision mirror or a windshield wiper, and among these kind of parts above mentioned, the engine, the suspension or the like can be mentioned as a work put together into in the subline.
Hereupon, as a conventional embodiment for conveying the work constructed in the subline to the assembly zone for the body of the automobile, there can be Japanese patent Laid-open publication 1994-135538 mentioned.
As for the work conveyance mechanism indicated in Japanese patent Laid-open publication 1994-135538, it is the work conveyance mechanism, in which the body of the automobile moving along a ceiling side path with being hung from the hanger device is set up an internal combustion engine to, and which consists of a floor side path that is laid on and one part thereof seems to repeat with the ceiling side path; a self-propelled trolley that is transferred along the floor side path; and a device of ascend and descend for rising the internal combustion engine loaded onto the trolley to the assembly zone.
With the work conveyance mechanism constituted in such manner, in the area that the ceiling side path is superposed on the floor side path, there are moved the hanger device and the trolley in one body combined, because a transmission part of the hanger device that is to move is engaged with a power receiving part of the trolley, and more, there is the internal combustion engine supplied in the assembly zone, to which the device of ascend and descend on the trolley is let rise.
However, it is necessary in the work conveyance mechanism for the trolley to be provided with means, by which the trolley is let self-propel and the internal combustion engine is let rise thereto so that the trolley has become large-scale and complicated in structure as well.
When the trolley extends in covered area and becomes complicated, the work efficiency falls to that extent because a working space of a worker assembling works to the body becomes narrow, and also there is a possibility to constitute an obstacle in safety of the work.
Beside, in order to let the work efficiency of automobile assembly line improve, it is necessary to be constituted that the floor side path is to be formed widely and there are many large-sized trolleys lying moved in a cycle.
However, when the trolley becomes large-scale and the floor side path is extended, there are problems that the use efficiency of the floor space is let fall and the degree of freedom according to the automobile assembly line is ruined as well.
Accordingly, it is a problem to be settled of this invention that the works can be conveyed by a simple constitution immediately and the work conveyance method and the work conveyance mechanism are offered, in which they do not ruin the work environment of a worker performing an assembly work to the body.
As for the invention according to claim 1 of the present invention in order to solve the problem above mentioned, it is the work conveyance method to convey the work constructed in the subline to the assembly zone, which includes: a delivering process, in which the work is delivered from the subline; a moving process, in which the work is moved parallel to the mainline in a lower part than the floor side of the mainline and supplied to the supply position that is underneath the assembling zone; a lifting process, in which the work is let rise from the supply position to the assembling zone.
With the work conveyance method constituted in this way, it is possible that the work delivered from the subline is supplied to the assembly zone from the part that is via under part of the mainline lying on the floor. Accordingly, because a conveyance mechanism such as a rail or a turn mechanism is not laid on the floor side of the mainline, a working area of a worker can be secured fully and the efficiency of installation working of the work can be let improve.
Besides, as for the invention according to claim 2, there is a work conveyance mechanism suggested, wherein the work constructed in the subline is conveyed to the assembly zone of the body in order to assemble the work to the body moving on the mainline, which comprises a moving means, in which the work transferred from the subline is let move under the floor of the mainline and supplied to a supply position under the assembly zone; a lifting means for assembly, in which the work is risen from the supply position to the assembly zone.
With the work conveyance mechanism constituted in this way, the work transferred from the subline can be moved under the floor of the mainline through the moving means. And also the work can be let rise to the assembly zone of the body from the lower part through the lifting means mentioned above. Accordingly, because the conveyance mechanism such as rail or a turn mechanism is not laid by the floor side of the main line, a working area of a worker can be sufficiently secured and the efficiency of installation work of work can be let improve.
Further, as for the invention according to claim 3, there is suggested the work conveyance mechanism according to the claim 2 in which a moving means possesses a slide mechanism, in which the work is moved parallel to the floor side under the same; and a lift means for transfer, in which the work can be moved up and down in order to transfer to the slide mechanism from the subline.
With the work conveyance mechanism constituted in this way, the work transferred from the subline is once took down in the lower part of the floor with the means for transfer and after moved therein, the work can be supplied to the assembly zone. Accordingly, even if the mainline and the subline are laid in the same floor side, the work constructed in the subline can be supplied to the body by way of the lower part of the floor.
And, as for the invention to be concerned with the claim 4, there is suggested the work conveyance mechanism according to the claim 3 in which the lift means for transfer is provided with a turn means for letting a direction of the work turn a fixed angle.
According to the work conveyance mechanism that is constituted in this way, the work can be smoothly assembled to the body even if the work transferred is different in a direction from that to be assembled to the body.
Besides, as for the invention according to claim 5, there is suggested the work conveyance mechanism according to the claim 3 or the claim 4, wherein the slide mechanism possesses a first slide part in which a pallet loaded with the work is to be moved to the supply position and a second slide part which is arranged a fixed distance below from the first slide part, and the lift means for assembly can move from the supply position to a return position at which the pallet is returned in the second slide part.
According to the work conveyance mechanism that is constituted in this way, it is possible that the work is carried in the first slide part and after it is assembled to the body, an empty pallet is moved in the second slide part, so that the empty pallet can be quickly return to the subline. Accordingly, because the pallet that is going to convey the work can be circulated quickly or smoothly, it is possible that the constructing of the work and the assembling of the work to the body are performed by the good efficiency.